Since the current Clade Ib wave began, the Democratic Republic of the Congo has reported over 32,000 confirmed and suspected Mpox cases with more than 870 deaths. WHO re-declared Mpox a Public Health Emergency of International Concern on August 14, 2024, specifically citing the emergence of Clade Ib as the driving concern. The situation has not improved.
Why does Clade Ib matter?
Clade Ib is a recombinant strain of the Monkeypox virus that emerged in eastern DRC and shows sustained human-to-human transmission through close physical contact, including sexual contact, household transmission, and healthcare settings. Unlike the Clade IIb strain responsible for the 2022 global outbreak, Clade Ib carries a higher case fatality rate and has demonstrated an ability to spread rapidly through populations with no prior Mpox immunity.
PandemicAlarm rates this event at 5/5 severity. Three factors drive that score: the novel recombinant strain with limited population immunity, sustained cross-border transmission, and a case count that continues climbing despite containment efforts.
Where has it spread?
Clade Ib has moved beyond the DRC into Burundi, Rwanda, Uganda, and Kenya. Burundi has been hit hardest among neighboring countries, reporting hundreds of confirmed cases since late 2024. Cross-border movement in the Great Lakes region makes containment extremely difficult. Mining communities, refugee camps, and urban centers with high population density have all seen transmission chains.
Travel-associated cases have appeared in Europe, Asia, and the Americas, though sustained transmission outside Africa remains limited as of March 2026. That could change. Each exported case is a seed for potential local transmission, particularly in communities where vaccination coverage is low and awareness of Clade Ib's clinical presentation is limited.
WHO's Disease Outbreak News reports on Mpox have emphasized the cross-border dynamic as a primary concern. Border screening alone cannot contain a virus with an incubation period of up to 21 days.
What about vaccines?
Vaccine supply is the critical bottleneck. The MVA-BN (Jynneos/Imvanex) vaccine is effective against Mpox, but production capacity is limited and global stockpiles are insufficient for the DRC's population of over 100 million. WHO and Africa CDC have coordinated vaccine donations, but deliveries have reached only a fraction of the at-risk population. DRC's healthcare infrastructure makes large-scale vaccination campaigns logistically challenging even when doses are available.
What Should You Watch in the Coming Weeks?
Three signals will determine whether this outbreak escalates further:
- Case trajectory in DRC. Weekly case counts have plateaued in some provinces but continue rising in others. A sustained national decline would be the first real sign of progress.
- New country introductions. Each border crossing into a country without active surveillance raises the risk of undetected transmission chains.
- Vaccine deployment pace. If vaccination reaches high-risk populations in the DRC and neighboring countries at scale, transmission should slow. Current delivery rates are not sufficient.
PandemicAlarm continues to rate this outbreak at the highest severity level. Until case counts show a sustained decline and vaccine deployment reaches meaningful coverage, that rating will not change.
Track the Mpox Clade Ib outbreak on the PandemicAlarm map for live data, case counts, and severity updates. For background on how outbreak severity is assessed, see our pandemic preparedness guide.